Tubular members, such as drill pipe or otherwise, can often become stuck in a wellbore during drilling or other operations, often referred to a “pipe sticking.” Pipe sticking can be a problem in the drilling and formation of wellbores that can cause non-productive drilling time. Pipe sticking can also trigger other drilling problems and sometimes may lead to a costly fishing operation to retrieve the stuck tubular, abandonment of the operation, or side tracking of the wellbore. Because of these costly problems, conventional techniques have been developed to predict pipe sticking in advance, for example, by evaluating properties related to an interface in a drilling mud and the tubular in the wellbore. The drilling mud, when in contact with a rock formation of the wellbore, may develop a mudcake (for example, drilling fluid that attaches to the wellbore under pressure). Conventional techniques, however, that are used to determine sticking or adherence properties of a mudcake to a rigid tubular (for example, a metallic drilling string) are often not reliable or accurate.
A fluid (for example, a liquid) may be used during a pipe unsticking operation in the wellbore. The fluid, typically called a “spotting fluid,” may help unstick the pipe from the wellbore. But as with mudcakes, conventional techniques that are used to determine sticking or adherence properties of a spotting fluid for freeing a rigid tubular (for example, a metallic drilling string) are often not reliable or accurate.